Microbiome variability and role of Candida albicans in site-specific dental plaques in orthodontic adolescent patients with white spot lesions

Introduction: We investigated changes in the supragingival plaque microbiome in orthodontic adolescent patients with white spot lesions (WSLs), and explored differences between demineralized and non-demineralized tooth surfaces and the degree of Candida albicans colonization.Patients/Materials and Methods: Supragingival plaques were obtained from 29 adolescent patients with WSLs (further categorized into WSL-WSL and WSL-Health groups based on the presence/absence of demineralization at the sampling sites, respectively) and 23 healthy adolescent orthodontic patients without demineralization. Supragingival plaque composition was evaluated using 16S rRNA sequencing and C. albicans colonization was identified through fungal culture and rDNA internal transcribed spacer region analysis.Results: For patients with WSLs, the supragingival microbiome on non-demineralized surfaces showed intermediate cariogenic potential between that of demineralized and healthy states but closer to that of the demineralized state. C. albicans exhibited greater propensity for colonization in patients with WSLs but without site specificity. C. albicans influenced bacterial composition, with Streptococcus mutans significantly enriched on the demineralized surfaces of patients with C. albicans infection.Conclusion: By elucidating the cariogenic potential of the supragingival plaque microbiome on non-demineralized tooth surfaces in orthodontic patients with WSLs, this study provides deeper insights into WSL pathogenesis, prevention, diagnosis, and risk assessment.